When I was young, my older brother could always outdo me in those activities kids did in the days before the internet. He could juggle, he could hacky sack, and most impressive of all he could do amazing tricks with a yo-yo. It wasn’t just that he had great yo-yoing skills—he was inherently better at understanding the trajectory of the Duncan Butterfly than I was.
I’ve often thought that his mastery of knowing exactly when…
